[miguelpanderland]

In a single step infusion mash what is the value of mashing out at a higher temp before sparging?  How do you know if you need to do this?

[denny]

If you batch sparge, there may be little value in terms of the traditional reason you do a mashout, which is to fix wort fermentability.  If you fly sparge, that might be different.  I seldom do a real mashout step any more, but I do sparge with hot enough water that my grain bed usually gets up to mash out temps.  I've found that raising the temp ensures complete conversion and has improved my efficiency.

[mabrungard]

The primary reason is to improve the overall mashing efficiency.  I see 8 or more points of additional gravity with a ~168F mash out step.  It further reduces the wort viscosity and extracts a little more out of the grist.  A mash out is always worth it in my opinion.

[miguelpanderland]

How does re-circulating the wort for improved clarity tie in with this?

Should I re-circulate after I've raised to mash-out temp or between the 60 min rest and the mash-out?

[tygo]

I've been thinking about this as well lately.  I batch sparge but by the time I runoff the wort into the kettle it's sitting there for quite awhile at around 140F (or lower).  I routinely raise the temperature at the end of the mash to around 160F to make help make sure I have complete conversion but there's likely still some beta left around even after that.

I have to imagine that whatever beta that's still around is continuing to do it's thing in the kettle until I start heating it up for the boil.

My attenuation tends to be a little on the high side of what I'm shooting for, even with higher mash temps, so with the next few batches I'm going to try a mashout rest at around 170F for about 10-15 minutes and see what that does.

[denny]

How does re-circulating the wort for improved clarity tie in with this?

Should I re-circulate after I've raised to mash-out temp or between the 60 min rest and the mash-out?

I only recirculate when I do a runoff.

[gordonstrong]

Beta amylase works at lower temperatures than alpha amylase.  The mnemonic I use is beta = before, alpha = after.

But I don't think that's the real issue.

Presumably, you're mashing out after conversion is complete.  The extra extract you get from mashing out has more to do with doing a better job of dissolving the sugars so they more easily run off than anything else.  You aren't converting more sugars; you're just leaving less of them in the mash tun.

[miguelpanderland]

How does re-circulating the wort for improved clarity tie in with this?

Should I re-circulate after I've raised to mash-out temp or between the 60 min rest and the mash-out?

I only recirculate when I do a runoff.

So when your moving the wort from mash tun to boil kettle?

[Kaiser]

The extra extract you get from mashing out has more to do with doing a better job of dissolving the sugars so they more easily run off than anything else.  You aren't converting more sugars; you're just leaving less of them in the mash tun.

I have been challenging the idea that the mash-out’s efficiency gain comes from less wort viscosity and better dissolving of sugars.

The gains that some brewers see from doing a mash-out are too big to be explained by this. I think that if you are seeing substantial efficiency gains from a mash-out (>5% or example) your mash wasn’t done converting before the mash-out. You can easily test this with a mash gravity test (http://braukaiser.com/wiki/index.php/Troubleshooting_Brewhouse_Efficiency#Determining_Conversion_Efficiency) . There have been a number of mashes in my past where the conversion efficiency was 90-95% before I did the mash-out and it was close to 100% 10-15 min into the mash-out.

FWIW, you can sparge with cold water w/o impacting your efficiency significantly.

Kai

[tygo]

For the people that are seeing a significant increase in efficiency by doing a mash out step I wonder if they'd get the same efficiency by stirring the mash alone and adding just enough hot water to maintain their mash temp.  It might be that the stirring improves the access of the enzymes to the remaining starches.

[bluesman]

This is an interesting discussion.

I haven't used a mashout as I was always led to believe it's not worth the effort in terms of added benefit but I am now uncertain. There isn't any convincing data that I have seen to prove one way or the other that it can increase efficiency or fermentability? I would employ a mashout if there was a significant benefit from the use of one.

Maybe Kai can conduct some experiments to the liking.  

[miguelpanderland]

Beta amylase works at lower temperatures than alpha amylase.  The mnemonic I use is beta = before, alpha = after.

But I don't think that's the real issue.

Presumably, you're mashing out after conversion is complete.  The extra extract you get from mashing out has more to do with doing a better job of dissolving the sugars so they more easily run off than anything else.  You aren't converting more sugars; you're just leaving less of them in the mash tun.

So then we can understand the mash out as an aid to the sparging process?  So maybe it's not something you want to do all the time but moreso with mashes the adjuncts that lend themselves to getting stuck?

[denny]

The extra extract you get from mashing out has more to do with doing a better job of dissolving the sugars so they more easily run off than anything else.  You aren't converting more sugars; you're just leaving less of them in the mash tun.

I have been challenging the idea that the mash-out’s efficiency gain comes from less wort viscosity and better dissolving of sugars.

The gains that some brewers see from doing a mash-out are too big to be explained by this. I think that if you are seeing substantial efficiency gains from a mash-out (>5% or example) your mash wasn’t done converting before the mash-out. You can easily test this with a mash gravity test (http://braukaiser.com/wiki/index.php/Troubleshooting_Brewhouse_Efficiency#Determining_Conversion_Efficiency) . There have been a number of mashes in my past where the conversion efficiency was 90-95% before I did the mash-out and it was close to 100% 10-15 min into the mash-out.

FWIW, you can sparge with cold water w/o impacting your efficiency significantly.

Kai

Kai, I agree with you.  I tried the cold sparge both with and without raising the mash temp first.  I found that raising the temp provided an efficiency boost with the cold sparge, but not raising the temp didn't.

[Kaiser]

Kai, I agree with you.  I tried the cold sparge both with and without raising the mash temp first.  I found that raising the temp provided an efficiency boost with the cold sparge, but not raising the temp didn't.

That nice. Did you post about this experiment. It seems more comprehensive than what I did.

Kai

[MDixon]

I'm about wiped out from travel, but let me be sure I am clear on what is being said. ?The sparge water in a fly sparge can be cool for post mashout sparging? ?What is cool? ?What were the procedures?

?Are you saying conversion efficiency would not suffer (understandable) or saying brewhouse/mashouse efficiency would not suffer (not so easy to grasp)?



FWIW - I have long wanted to sparge using hot water from a tankless hot water heater ~130F to see what would happen. I have the ability to now do just that, but haven't had the time to try it. I was thinking of mashing out and then sparging with the 130F water. The beauty is it would only take a small amount of water discard before the temp reached max temp and then no additional heat would be needed from a burner.